Air and water heating furnace



Dec. 12, 1950 c. E. RlczE 2,533,692

AIR AND WATER HEATING FURNACE Filed Dec. 31, 1946 v 3 Sheets-Sheet 1 IN VEN TOR.

3 Sheets-Sheet 2 C E RICE AIR AND WATER HEATING FURNACE Filed Dec.- 31, 1946 Dec. 12, I950 Dec. 12, 1950 c:. E. RICE AIR AND WATER HEATING FURNACE 3 Sheets-Sheet 3 Filed Dec. 31, 1946 INVENT 0R. Clq /iarzE-fiwe,

Patented Dec. 12, 1950 U N ITE D STATES PATENT OFFICE AIR. AND? WATER HEATING FURNACE Clayton E. Rice, Chicago, Ill'.

Applicationlliecember 31, 1946, Serial No..7.l9,359.-

lClaim. 1

This invention relates to a. new and improved heating system and more particularly to apparatus whereby the heat derived from burning fuel serves to raise the temperature of bothwater and air forheating purposes.

The apparatus for carrying out this heating. methodv comprises a boiler by which water is heated either to producesteam for steam heating or to a temperature less than that necessary for steam generation so that it may be used for hot water heating. In addition to this water heating, I provide means whereby air. may be heated simultaneously so that a very high percentage of the heat contained in the products of combustion is absorbed for useful work. and stack temperatures are low.

My construction involves the use of relatively small, self-contained units which may be assembled in any desired number to provide heating for buildings or spaces of different sizes.

It is an object of the presentinvention to provide new and improved heating apparatus adapted to absorb a high percentage of the heat in flue gases or products of combustion.

It is a further object to provide a construction in which the heat is transferred both to. water and to air fo space heating or industrial heating purposes.

It is also an object to provide a multiple unit construction which may be assembled inany desired number for conjoint use to heat any specific area.

It is another object to provide a multiple unit construction in which the different units may be used selectively in desired numbers dependent upon the amount of heat required.

It is an additional object to provide a construction which is simple in design and operation and adapted for commercial production and use.

Other and further objects will appear as the description proceeds.

I have shown certain preferred embodiments of my invention in the accompanying drawings, in which- Figure 1 is a vertical section taken from front to back of a single heating unit;

Figure 2 is a vertical section extending across a plurality of units;

Figure 3 is a front face View, partly broken away, showing a plurality of units;

Figure 4 is a front face view, partly broken away, on a reduced scale showing a plurality of units with associated hot air conduits; and

Figure 5 is a View similar to Figure 4,.but showing a single unit, partly in section.

Referring first to Figure 1, the construction comprises units having front wall plates II and rear wall plates l2 which extend vertically. The lower portions of the plates II and I2 are joined adjacent their lower ends by horizontal plates l3. and I4 between Whichis. placed insulation l5 2 to retain heat and. also to prevent damage to. the supportin floor. The water supply line. I is controlled by valve I1 andis connected through:- T IE. to feed pipe I 9 and to the lower water.v drum 20' which is supported on the endv plates. H and I 2. This drum 20. is providedwiththe; fusible safety plug 31. The drum 20 is connectedby the U 2! extending through plate. H. to the serpentine pipe 22 which has a number of horizontal passes and joins the upper. drum 2'5 through the upper U 21.

The unit is shown asv heated by meansof the gas burner 28 which is located in the combus tion chamber 29 and isfed through pipe 3t, controlled by valve 3!, from gas header 3.2-. An automatic valve 33 is located in pipe'iill, this Valve having a' thermostatic. element 34' extending into. U 2!- and into contact with the water therein.v The pilot light 35 is connected to pipe 30 by pipe 36 at a point behind valve 33. The particular type of burner and control shownigillustrative only and its details form. no part. of the present invention. Any suitable form of. burner or heating means may be used in con-- nection with the heating unit and the. apparatus shown is of standard construction.

As shown in Figure 2,.a fire tube 38'with lateral flanges 46 secured thereto is located above the lower pass of pipe 22. The lower portion of. this tube 38 between flanges 46 is perforated to receive the. products of combustion which pass through return fitting. 39'and into the large pipe 40 which encloses the second pass 23 of pipe 221 The pipe 40 carries arcuate baflles 4| which are alternately placed above and belowthe pipe pass 23, the bafiies being. secured together by rods 56'. These baffles 4i cause the flue gases to take a' tortuous path in pipe 40 and increasesthe. heat transfer both through the water carrying pass 23 and through the outer wall of" pipe-ldto'the air which surround it. The baflles 41 also serve to maintain the smaller pipe properly centered in the larger'flue 40. These bafiies' ll are notched at their top and bottom portions, as shown at 12 in Figure 2; to prevent gas pockets. The pipe 40 is provided with fins'42 to increases, the heat transfer to the air around the pipe.

A return fitting 33 at the front end of the unit is similar to-the fitting 39 and returns the flue gases to-the next pass 44 of the flue pipe which'is similar to pipe Ail; This pipe 44 encloses thenext pass 24' of water pipe 22 and is provided with the baffles 45 similar to baffles 41, The construction issimilar in the additional passes of the pipe 22 containing water or steam and their surrounding pipes carrying the flue gases or products of combustion.

The top pass 18 of the water tube has been made larger than the lower passes t provide-a smaller space for passage of the flue gases in the top pass 52- of the fire tubes. This is-provided topartially choke orslowdown-the flow of th 'fl uez gases so as insure proper transfer of heat to the water or steam in the water tubes. It will be apparent that the flue gases will be much cooler at this point and consequently will be much reduced in volume so that a substantial reduction in flue area may be provided without adversely affecting the draft and flow to the stack.

The upper drum 26 is connected to the balancing water pipe 41 which joins the T 18. This pipe 41 carries a water column when the boiler is used for steam production or vapor heating and is provided with the water gauge 48 and the gauge cocks H3. A pressure gauge 49 which may be graduated to show steam pressure or, if the boiler is used for hot water heating, may be graduated in feet to show the extent to which the heating system is filled with water. The drum 26 is also provided with the pressure relief valve 78 which may be of an usual construction.

The upper drum 2% is provided with the outlet pipes 56 and 5! through which steam or hot water, depending upon the operation of the boiler, is drawn off for use. The topmost pass 52 of the outer pipe carrying the flue gases or products of combustion is connected to the housing 53 which is connected by pipe 54 to fine 55. This flue 55 is connected to a stack or chimney which has not been shown.

A single unit heater has been shown in Figure 5. The unit has the side walls 51 and 53 which extend upwardly to form a housing about the upper drum 2%, A hot air pipe 68 leads from the housing to carry the heated air to a distribution system where it may be used for any desired purpose such, for example, as space heating Or indu.,-

trial drying. Air to be heated is forced into the heater housing by fan 53 and passes through pipe 6| which joins the housing immediately above the fire wall 38.

A multiple unit system is shown in section in Figure 2 and in elevation in Figure 4. The assembly has side walls 63 and 64 which enclose the group of units and has a transverse top wall 55 which extends below the drums 26. The spaces between the fire walls 38 may be closed by angle irons 66 so as to prevent entry of flue gases into the air space. Air to be heated is forced into the air chamber by fan 6'! through passage 68 and the hot air is carried from the opposite side of the upper portion of the chamber through passage 69.

In the preferred form of construction means are provided to cause the air to take a definite tortuous path over the fire tubes and fins when a multiple unit heater is used such as shown in Figures 2, 3 and 4;. As shown in Figure 4, the air passes from passage 58 across the housing to the right above the lower fire tube 38 and below a horizontal wall 70 formed of a sheet of metal resting on the top of the fins 32 carried b the fire tubes immediately below the wall. A return housing 15 at the right carries the warmed air up and around the right end of wall 14 and it passes to the left over wall 74 and below a similar wall 16. The return housing ii on the left returns the air above wall 18 and below the top wall 65 to the outlet housing 69.

It will be apparent that the construction comprises a plurality of identical units so that a heating plant of any desired capacity may be assembled. Thus, one standard type of unit may be used when assembling heating plants for large or small areas. This greatly reduces production costs and also reduces the stock of 4 units which need be carried on hand for distribution or replacement.

A further feature of the unit type of construction is that any desired proportion-of the units may be used. Where the apparatus is used for space heating, only a portion of the units may be used in mild weather. In industrial heating applications, the number of units in use may be varied in proportion to the work load.

The construction shown may be assembled in any desired manner. The water tube may comprise a plurality of sections welded or brazed together. The tube may comprise standard pipe sections and pipe fittings. The end fittings joining the ends of the fire tubes are preferably removable. The baifies which support the water tube in the fire tubes may be connected together by means of spacing rods. Thus, they may be removable from the front or back of the unit when the end fittings or housings are removed. This will facilitate cleaning the fire flues. The entire outside and particularly the lateral Walls of the unit or assembly may be covered with any usual type of insulation.

While I have shown certain preferred embodiments of my invention, these are to be understood to be illustrative only as it is capable of variation to meet differing conditions and requirements, and I contemplate such modifications as come within the spirit and scope of the appended claims.

I claim:

A heating apparatus assembly comprising a plurality of units, said units comprising relatively narrow front and back walls connected at their lower portions by a fire wall dividing the space between the front and back walls into a lower combustion chamber and an upper air heating chamber, side walls for the heating assembly joining the outer edges of the outer front and back wall units and fire wall units, a top Wall connecting the front, back and side walls, a fire tube assembly in each unit communicating at its lower end with the combustion chamber and having a plurality of forwardly and rearwardly extending passes in the upper air heating chamber, said fire tube passes being spaced apart to provide air passages therebetween, a water tube assembly in each unit including at 3 least one pass extending within the combustion chamber and a plurality of passes extending within fire tube passes in the upper chamber, means for introducing air into the lower portion of the air heating chamber through a side wall, baffles in the air heating chamber extending alternately from each side wall toward the other in staggered relation between fire tube passes, and means for withdrawing heated air from the upper portion of the assembly.

CLAYTON E. RICE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

